Evaluation of HLA expression on gametogenic cells isolated from human testis

Human germinal cells were isolated using a combined mechanical method and enzymatic digestion of testicular tissue. The attempt to fractionate the testicular cells by centrifugation in the continuous and discontinuous Percoll gradient was undertaken. The homogeneous (100%) fraction of late spermatids and enriched fractions of spermatocytes (up to 60%) and round spermatids (approx. 66%) were obtained. Cell-binding radioimmunoassay (CB-RIA) was used to evaluate the HLA expression both on heterogeneous suspensions and enriched fractions of testicular, germ cells using mouse monoclonal antibodies directed to Class I (HLA, -A, -B, -C) and Class II (HLA, -DR) determinants of MHC (main histocompatibility complex). Consistently negative results were obtained as well for heterogenous populations of germinal cells as their fractions in respect to both Class I and Class II antigenic determinants of HLA system.